// $Id: DBReader.java,v 1.4 2003/10/07 21:46:00 idgay Exp $

/*									tab:4
 * "Copyright (c) 2000-2003 The Regents of the University  of California.  
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement is
 * hereby granted, provided that the above copyright notice, the following
 * two paragraphs and the author appear in all copies of this software.
 * 
 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
 * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
 * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
 *
 * Copyright (c) 2002-2003 Intel Corporation
 * All rights reserved.
 *
 * This file is distributed under the terms in the attached INTEL-LICENSE     
 * file. If you do not find these files, copies can be found by writing to
 * Intel Research Berkeley, 2150 Shattuck Avenue, Suite 1300, Berkeley, CA, 
 * 94704.  Attention:  Intel License Inquiry.
 */

package tools.packet;

import java.sql.*;
import java.util.*;

/**
 * Class for reading packets from a database. Unfinished.
 */
class DBReader {

	Connection db = null;
	Statement st = null;
	private static final String urlMYSQL = "jdbc:mysql://127.0.0.1:3306/packets";
	private static final String urlPSQL = "jdbc:postgresql://127.0.0.1:16882/motes";
	private String m_usr = "bwhull";
	private String m_pwd = "";
	private boolean POSTGRESQL = true;
	public static final boolean DEBUG_QUERIES = true;
	public static final boolean DEBUG = true;
	public static final int FIELD1_POS = 1;
	public static final int FIELD2_POS = 2;
	public static final int FIELD3_POS = 3;

	private ResultSet m_rsPackets = null;

	DBReader(String user, String pass, boolean ps) {
		m_usr = user;
		m_pwd = pass;
		POSTGRESQL = ps;
		throw new UnsupportedOperationException("not finished");
	}

	public boolean Connect() {
		try {
			System.out.println("Connecting to database");

			if (POSTGRESQL) {
				Class.forName("org.postgresql.Driver");
				db = DriverManager.getConnection(urlPSQL, m_usr, m_pwd);
			} else {
				Class.forName("org.gjt.mm.mysql.Driver");
				db = DriverManager.getConnection(urlMYSQL, m_usr, m_pwd);
			}
			db.setAutoCommit(false);
			// st = db.createStatement( ResultSet.TYPE_SCROLL_SENSITIVE,
			// ResultSet.CONCUR_UPDATABLE );
			st = db.createStatement();
			return true;
		} catch (Exception ex) {
			ex.printStackTrace();
			return false;
		}
	}

	public void Close() {
		try {
			if (st != null) {
				st.close();
			}
			if (db != null) {
				db.close();
			}
			st = null;
			db = null;
		} catch (Exception e) {
		}
	}

	public byte[] NextPacket() {
		System.out.println("DBReader: getting next packet");
		if (st == null) {
			System.out.println("DBReader: Unable to write packet\n");
			return null;
		}

		byte[] packet = null;

		try {
			if (m_rsPackets == null) {
				System.out.println("DBReader: executing read query");
				m_rsPackets = st
						.executeQuery("SELECT * FROM packets ORDER BY rcvdtime asc");
			}
			if (m_rsPackets != null && m_rsPackets.next()) {
				System.out.println("DBReader: extracting payload");
				packet = m_rsPackets.getBytes("payload");
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return packet;
	}

	public Timestamp GetTimestamp() {

		if (m_rsPackets == null) {
			System.out.println("DBReader: must first read a packet\n");
			return null;
		}

		Timestamp ts = null;

		try {
			if (m_rsPackets != null) {
				ts = m_rsPackets.getTimestamp("rcvdTime");
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}

		return ts;
	}

}
